We will examine the effects on appetite of a moderate dose of dronabinol (oral delta^9 THC). At the start of each session, subjects will eat a special lunch in the CRC and then will return to our laboratory. One and 1/2 hr after consuming the lunch, subjects will ingest either a dronabinol (7.5 mg) or placebo capsule. Appetite and subjective effects questionnaires will be administered at baseline (immediately prior to drug administration) and at 0.5-hr intervals over the course of a five hour session. At the end of the session, subjects will go to the CRC and be given a sampling tray of foods. Nutrient analysis of foods eaten will be performed.